At present, dunning call service and wake-up call service have been developed in fixed intelligent network, during these operations, the problem needs to be solved most urgently is how to actively establish calls by SCP and then play back a recorded voice announcement for certain subscribers. In prior fixed intelligent network technology, Initiate Call Attempt (ICA) for asking Service Switching Point (SSP), the interface equipment between server switching layer and intelligent layer, to create voice channels to subscribers has been defined through Intelligent Network Application Protocol (INAP), and then recorded voice announcements such as “no enough balance in your account, charge immediately please” can be played back to subscribers via the voice channel.
Nevertheless, these operations having wide usage and high practical value in fixed intelligent network can not be realized in the prior mobile intelligent network, because calls to the subscribers cannot be establish actively with the Customized Application for Mobile Network Enhanced Logic (CAMEL) protocol in mobile intelligent network corresponding to the INAP protocol in fixed intelligent network. In this way, the development of dunning call service and wake-up call service in mobile intelligent network services is limited.